It's a pleasure to be here today and to open this very important conference on the economics of HACCP. HACCP is playing a prominent and growing role in establishing public policy for food safety within the U.S. Department of Agriculture (USDA) and the Food and Drug Administration (FDA). Today, I would like to provide you with an overview of our research needs in the food safety strategy for meat, poultry, and egg products--the foods USDA regulates.

USDA's overall public health goal, as it relates to food safety, is to reduce the incidence of foodborne illness associated with meat, poultry, and egg products. Several years ago, following an outbreak of foodborne illness on the West Coast, USDA began a strategy for change to meet this public health goal.

Since then, several major initiatives have been implemented, including safe handling labels on products, expanded testing for microbial pathogens, performance standards for pathogen reduction, and mandatory Hazard Analysis and Critical Control Points (HACCP) systems to prevent and control contamination. Our strategy addresses the entire farm-to-table continuum because a multi-faceted approach is necessary to solve today's complex food safety problems.

We have embarked on this strategy, and implemented these changes, with full recognition that there are many gaps in our knowledge about the hazards in food, the risks they pose, the interventions needed to address them, and the benefits and costs of interventions. But we needed to make regulatory and policy decisions based on the best information available today, recognizing that adjustments in those policies might be needed as new information becomes available.

This is not a new situation for public health or regulatory agencies. Looking back at history, we can find many examples where action on a public health problem has been taken before all of the answers are in. In 1849, a large outbreak of cholera occurred in London, and John Snow, a founding member of the London Epidemiological Society, set out to find the source. By studying the distribution of cases, he was able to conclude the problem was coming from a well in one part of town. To control the epidemic, he simply took the handle off of the pump. It was not until some 34 years later, in 1883, that the cholera vibrio was identified, but he was able to make the association between the disease and the source--and end the epidemic--without knowing all of the details.

Risk Assessment Applications

In the almost 150 years since that cholera epidemic, public health researchers have developed a variety of methods to help decision-makers understand and manage health hazards. Risk assessment is one method that is playing a major role in helping us to further improve food safety and in planning future initiatives. It has the potential to improve our ability to reduce foodborne illness in a number of ways.

Risk assessment provides structured information that allows risk managers to identify interventions that can lead to public health improvement and provides a basis for them to use in weighing the options. These options include regulatory action when necessary, but also include a broad range of options such as voluntary activities, educational initiatives, and research to close critical data gaps. In a few moments I will talk more about how we are using a microbial risk assessment for Salmonella Enteritidis in eggs and egg products in making risk management decisions.

Risk assessment also can be used to identify data gaps and target research that should have the greatest value in terms of public health impact. We have already begun the process of identifying research needs based on public health impact, but risk assessments will allow us to continue this work in a more quantitative manner. I'll talk more about this approach to research priority-setting as well.

Risk assessments also will help industry to develop more effective HACCP plans. We are in the process of implementing a HACCP requirement in all plants that slaughter and process meat and poultry. For the future, risk assessments will help plants to scientifically develop HACCP plans.

For instance, plants can use a risk assessment to help identify hazards that are reasonably likely to occur. The best information plants may have now is qualitative--whether a hazard presents a high, medium, or low risk. The real benefit to this change is that a hazard would be defined in terms of the risk of an adverse human health consequence, rather than in terms of contamination on a carcass or product.

Risk assessments also play an important role in international trade by ensuring that countries establish food safety requirements that are scientifically sound and by providing a means for determining equivalent levels of public health protection between countries. Without a systematic assessment of risk, countries may set import requirements that are not related to food safety, and could create artificial barriers to trade. Recognizing the importance of this science-based approach to fair trade, the World Trade Organization requires each country's food safety measures to be based on risk assessment. The Codex Alimentarius Commission, which establishes international food safety standards, is now developing principles for using risk assessment in establishing such standards.

Challenges of Microbial Risk Assessments

While there are many potential applications for risk assessment, we are realistic about the challenges of conducting formal, quantitative risk assessments. Risk assessment has its roots in toxicology and carcinogenity studies, and its application to microbial pathogens poses some significant challenges. One challenge, of course, relates to the fact that unlike chemical, environmental, or toxicological contaminants, bacteria can multiply and produce toxins as conditions change as food moves through the farm-to-table continuum. Fortunately, researchers are making progress in developing the predictive models and other tools that will meet the technical requirements for quantifying estimates of risk.

In addition to this technical difficulty, we have many data gaps that limit the precision we can achieve through risk assessments. For instance, we have little information to accurately estimate the relationship between the quantity of a biological agent and the frequency and magnitude of adverse human health effects, particularly as this might relate to susceptible sub-populations. We also have limited information on exposure assessment--the foods consumed by populations and the probability of contamination.

Current Risk Assessment Activities

Despite these challenges, I believe we are making good progress, and I would like to describe some of the risk assessment activities in which USDA is involved.

First, we have created a structure within USDA for addressing risk assessments. The Food Safety and Inspection Service (FSIS), the USDA agency with responsibility for the safety of meat, poultry, and egg products, has undergone a reorganization that establishes a new Division of Epidemiology and Risk Assessment within the Office of Public Health and Science. This division will ensure that the risk assessment paradigm is incorporated into the spectrum of work throughout the agency. The reorganization also created an Office of Policy, Program Development and Evaluation that houses our food safety risk managers. This separation of risk assessment from risk management activities will ensure the scientific integrity of the process and the products of agency-conducted risk assessments.

Also within USDA is the Office of Risk Assessment and Cost-Benefit Analysis headed by Dr. Nell Ahl, which is responsible for ensuring that major regulations proposed by USDA are based on sound scientific and economic analysis. For regulations having an annual economic impact of at least $100 million in 1994 dollars, USDA must conduct a thorough analysis that makes clear the nature of the risk, alternative ways of reducing it, the reasoning that justifies the proposed rule, and a comparison of the likely costs and benefits of reducing the risk.

USDA's Economic Research Service (ERS) is playing an important role conducting economic research on the costs of foodborne illness and in analyzing the costs and benefits to perform cost-benefit analyses of interventions to control pathogens.

Second, in addition to establishing a structure within USDA to address risk assessment, we also are encouraging research to develop predictive models and other tools that will meet the technical requirements for conducting risk assessments.

This work is being done through the Interagency Risk Assessment Consortium, which was established as part of President Clinton's Food Safety Initiative. The Consortium links all federal agencies with risk-management responsibilities for food safety to collectively advance the science of microbial risk assessment.

Third, we are working in conjunction with other government agencies and academia to conduct risk assessments addressing meat, poultry, and egg products.

This summer, we plan to begin a risk assessment for E. coli O157:H7 in hamburger. We have already done some important developmental work in designing a structure for conducting such an assessment. In addition, we recently completed in conjunction with USDA's Agricultural Research Service a study to determine the prevalence of premature browning of hamburger, and the data from this study will feed into the larger risk assessment for E. coli O157:H7.

In addition to this risk assessment for E. coli O157:H7 in hamburger, we have entered into a cooperative agreement with Harvard University's School of Public Health for a risk analysis of Bovine Spongiform Encephalopathy (BSE). No cases of BSE have been identified in the United States, but we believe it would be beneficial to analyze and evaluate USDA's current measures to prevent it and identify any additional measures that may be warranted to ultimately protect the public health.

Risk Assessment for Salmonella Enteritidis

I would like to take a few minutes to discuss the risk assessment recently completed on Salmonella Enteritidis (SE) and eggs and egg products. This is our first quantitative, farm-to-table microbial risk assessment, and I expect it to serve as a prototype for future risk assessments. The final document will soon be available on the FSIS web site at www.usda.gov/fsis. The scientists who conducted the risk assessment formally presented the results at a USDA-sponsored Risk Forum on Friday last week, in Washington, DC.

The risk assessment was conducted by a multi-disciplinary team with members from government and academia. The team was led by Dr. Roberta Morales, who was at that time on contract to USDA, and Dr. Richard Whiting, who was then with USDA's Agricultural Research Service. A number of USDA agencies had members on the team--the Agricultural Research Service, the Animal and Plant Health Inspection Service, the Economic Research Service, the Agricultural Marketing Service, and the Office of Risk Assessment and Cost-Benefit Analysis. From the Department of Health and Human Services, we had representation from the Food and Drug Administration and the Centers for Disease Control and Prevention. Two academic institutions--North Carolina State University and Delaware Valley College--were also involved.

We began the SE risk assessment in December 1996 in response to an increasing number of human illnesses attributed to the consumption of contaminated eggs. Data from the Centers for Disease Control and Prevention indicate that SE is one of the most commonly reported causes of bacterial foodborne illness in the United States and has been increasing since 1976. This increase has occurred despite a variety of initiatives we, and the industry, have had underway to address the SE problem.

The SE risk assessment has several objectives. First, it is intended to characterize, using the data available, the adverse public health effects associated with consuming shell eggs and egg products contaminated with SE. A second goal is to identify data needs and prioritize future data collection efforts to reduce the areas of uncertainty with the assessment. Third, the risk assessment is designed to identify and evaluate potential risk reduction strategies, using a farm-to-table model.

The risk assessment extends from production to consumption of shell eggs and processed egg products. This reflects our belief that to appropriately address the problem of SE, a comprehensive strategy with multiple interventions is needed. Thus, the risk assessment has several modules, reflecting each stage of the farm-to-table continuum.

The first module--shell egg production--simulates the daily SE-positive egg infection frequency for U.S. commercial flocks. The second module--shell egg processing and distribution--follows the shell eggs from collection on the farm through processing, transportation, and storage. The third module--egg products processing and distribution--tracks the change in numbers of SE organisms in egg processing plants from receiving through pasteurization. The fourth module--preparation and consumption--describes exposure from the consumption of eggs and egg-containing foods that are contaminated with SE. The fifth module--public health outcomes--links exposure to eggs and egg products containing SE with the public health outcomes of morbidity and mortality.

It would take more time than I have available today to present the findings of this risk assessment, so I will briefly review some of the results and some of the important principles we learned from the process. I urge you to take a closer look at the entire document.

First, we now know more about the incidence of illness attributed to SE in shell eggs and egg products. Out of an average of 46.8 billion shell eggs produced per year in the United States, we estimate that, on average, 2.3 million eggs contain SE. While this translates into a very small percentage of contaminated eggs, the implications for human health are quite significant--consumption of these eggs results in an average of 661,633 human illnesses per year. We predict that 94 percent of these individuals recover without seeking medical care.

These numbers, however, are associated with a degree of uncertainty, largely because of the data gaps encountered. This relates to the second thing we learned from the risk assessment--that there is much more we need to know about shell eggs and egg products. We encountered many data gaps during the risk assessment process, which required us to make a number of assumptions.

For example, we need more information on the association between environmental factors and management practices with SE-positive flocks on the farm. We need cooling curves in order to predict the temperature of an egg at a specified time during the processing of shell eggs, given the initial temperature of the egg, ambient air temperature, and packaging characteristics. We also need more information about industry practices regarding the storage of eggs, and consumer practices regarding the preparation and consumption of eggs. These are just a few of the many data gaps identified.

Another major result from the risk assessment is that we now have a farm-to-table model--a computer program--we can use to determine the effects of specific interventions on the incidence of illness. In fact, as part of the risk assessment, the team evaluated a number of possible interventions on the expected number of human illnesses. They included shell egg cooling, diverting eggs from flocks with a high prevalence of SE-positive hens to breaker plants for pasteurization, and reducing the prevalence of SE-positive flocks. The potential uses for such a model in determining appropriate risk reduction strategies are many.

From this exercise, we also learned a very important principle. That is, a broadly based policy is more likely to be effective than a policy directed solely at one area of the egg production to consumption chain. That is why our strategy to address the problem of SE in eggs will be a multi-faceted strategy that addresses the entire farm-to-table chain.

Risk Management

Now that we have completed this risk assessment, the results will be available to risk managers as they develop a comprehensive strategy to address the problem of SE in eggs and egg products.

On May 19, we published, in conjunction with the Food and Drug Administration (FDA), an Advance Notice of Proposed Rulemaking (ANPR) in the Federal Register to initiate a comprehensive and coordinated process of addressing the SE problem in shell eggs and to solicit input from the public on strategies. This ANPR was published jointly by USDA and FDA because we share the responsibility for egg safety.

A number of other initiatives are already underway by USDA and FDA to address the safety of both shell eggs and egg products. For instance, FSIS is in the process of developing a proposal to mandate HACCP in egg processing plants, similar to the requirement that now exists for meat and poultry plants.

The risk assessment will be very useful as we proceed with this process of risk management analysis. While the process of risk management analysis is not new in FSIS, what is new is that we now have a farm-to-table model with which we can predict the effects of possible interventions and determine which provide the best return in terms of public health protection. Our risk managers will evaluate all of the options available and select appropriate ones based on factors such as the level of risk, feasibility, and economic costs.

While we have issued the risk assessment as a final report, we must be careful not to consider the risk assessment itself as final. It is a fluid entity that will continually be updated as new information becomes available, making the risk assessment even more valuable as a management tool.

Risk Communication

I have not yet touched upon the third component of risk analysis--risk communication. Our experiences with the SE risk assessment reinforced some principles of risk communication, and I would like to share those with you.

Good communication is important from the very beginning of the risk assessment. Everyone--the affected industry, the public health and scientific communities, consumers, and regulators--must have a clear understanding of the project and the opportunity to provide input. In particular, risk managers must be brought in at the beginning stages to ensure that there is agreement on the goals of the project, and communication between the risk assessors and managers should continue throughout the process.

Stakeholder input is imperative throughout the risk assessment process. We held several meetings to solicit input from stakeholders during out risk assessment, and we found it very important to the integrity of the project. We intend to continue this open process as risk management decisions are made.

Communication with the public will also be important as we determine what educational strategies are necessary to reduce the risk of foodborne illness from SE in shell eggs and egg products. It will be extremely important that we communicate risks to the public in a proper context and in a helpful manner, with a well-thought-out and consistent message.

We are getting some experience with risk communication right now, in fact. We are using a study conducted by the Agricultural Research Service on the premature browning of hamburgers to determine what should be the appropriate message to consumers on how to determine the doneness of hamburgers. We must balance the science with practicality--a science-based recommendation is of little use unless consumers will follow it.

Research

Research is very important to the success of these regulatory and non-regulatory food safety initiatives. In order to effectively address the safety of meat, poultry, and egg products, we need to know more about the hazards in these foods and their relation to illness.

Our programs must be responsive to new information and new data. And because our food safety strategy has broadened to cover the farm-to-table continuum, our research agenda must also address the entire continuum.

On a very basic level, we must encourage fundamental research on the ecology of human pathogens in animals. We need to know, for example, how these pathogens grow, develop and colonize in livestock; how they acquire the ability to produce toxins; and how they acquire antibiotic resistance. This fundamental science will set the stage for potential breakthroughs in vaccines, competitive exclusion, and other preventive approaches.

We also need research to help us make regulatory decisions that are based on the most current science. HACCP provides an important framework for improving food safety within plants, but it must be combined with science-based performance standards that HACCP systems are designed to achieve. Our ultimate goal is to base performance standards on quantitative risk assessments. We need extensive, new data to conduct these risk assessments.

Where will this data come from? Agricultural research is now a shared responsibility of both the public and private sectors. The Federal government has played a major role in supporting agricultural research for over a century. It supports intramural research through the Agricultural Research Service, the Forest Service, and the Economic Research Service. It supports the collection of valuable statistical data through the National Agricultural Statistics Service. It also funds extramural research at State institutions, which is administered by the Cooperative State Research, Education, and Extension Service. This strong, federally-funded research base is needed because there are research problems and issues of national importance that may receive too little attention from individual States or regions. This research also serves the needs of the regulatory and action agencies.

Despite the extensive investments made by the Federal government, the lack of growth in public agricultural research expenditures--Federal and State--constrains the ability of the public agricultural research system to respond to new demands. Federal expenditures have not really grown in real terms since the mid-1970's. The recently enacted research title reauthorization will help to turn around this dismal situation. It provided $120 million per year in competitive grants for the next 5 years from mandatory funds, and food safety is one of the priority areas.

At the same time, we know that over the past 30 years, the importance of the private sector in both funding and conducting agricultural research is growing.

Agricultural research will continue to require involvement by the Federal government in areas where private incentives are weak, and many aspects of food safety research fall into this area. But I believe the growing importance of food safety and the impact it can have on business are providing a growing incentive for private industry to support fundamental, as well as applied, food safety research. I believe this mutual interest in food safety research provides opportunities for partnerships in the future.

Food Safety Research Agenda

FSIS is not a research agency, but it needs to identify research that is needed to improve food safety. That means reaching out to the research agencies within the Federal government, and to scientists in academia and the private sector. For that reason, in 1997, the Agency developed a Food Safety Research Agenda as one means of communicating with those outside the Agency about its priorities in food safety research. As a first step, FSIS established a Food Safety Research Working Group, which was composed of government scientists representing a broad base of expertise.

The working group used human health effects as the basis for determining FSIS research needs. Using the criteria, the group reached a consensus on the major research questions that needed to be answered. They identified general research questions as well as research needs that are unique to the following pathogens--Salmonella, Campylobacter, Listeria, and Enterohemorrhagic E. coli, including E. coli O157:H7.

Criteria Used to Develop the research Agenda

1. Incidence of Adverse Health Outcome

2. Causes of Adverse Health Outcome

a. Chemical
b. Physical
c. Biological

3. Linkage (etiological/vehicle linked to food)

4. Outcomes

a. Sequela
b. Deaths
c. Distribution (demographics/populations)
d. Costs

* Medical
* Productivity Losses

e. Public Sensitivity/Perceptions

These are the questions from the research agenda that were developed for E. coli.

E. coli Research Questions

1. What is the incidence of EHEC and E. coli O157:H7 disease/infection in humans and animals in the United States? What is the relative incidence among different subpopulations?
   
   
2. What are the virulence factors associated with EHEC? Are all Shiga toxin-producing E.coli (STEC) pathogenic for humans, i.e., are all STEC also considered EHEC? Which virulence factors are associated with bloody diarrhea, hemolytic uremic syndrome, or other sequelae?
   
   
3. How do EHEC colonize both animals and humans?
   
   
4. What is the infectious dose and the dose-response relationship of EHEC and E. coli O157:H7 for humans and animals? Does a threshold exist below which illness does not occur? Is a zero tolerance standard supportable by scientific evidence? Can dose response data calculated for Shigella sp. or S. dysenteriae type 1, be used for EHEC and E. coli O157:H7?
   
   
5. What is known about the microbial ecology of EHEC and E. coli O157:H7? What are the environmental reservoirs for EHEC and E. coli O157:H7 along the farm-to-table continuum? What are survival and growth characteristics before and after cooking?
   
   
6. Should we be screening E. coli from human disease, and/or from food, for toxin production, or for the presence of stx, eae, hyl, EHEC plasmid, adhesins, etc.? Should we be screening human fecal specimens and/or foods for the presence of Shiga toxins?

The questions that the working group developed are important for several reasons. First, because the groups used public health criteria as a means of determining research priorities, we can consider the pathogens identified by the group to be the major pathogens of concern for future research.

Second, the research agenda reflects the direction taken by the President's Food Safety Initiative. The initiative supports the use of risk assessment as a means of characterizing risks to human health associated with foodborne hazards and assisting regulators in making decisions about where in the food production and marketing chain to allocate resources to control those hazards.

The challenge for the future will be to integrate all of the research needs stated in the FSIS Research Agenda and the President's Food Safety Initiative into an operational plan that reflects the emphasis on cooperation and partnerships.

To assist in this process, an interagency working group convened by the White House Office of Science and Technology Policy has been working to coordinate Federal research priorities and planning. The goal of this working group will be to develop a coordinated Federal food safety research plan that will extend to our research partners in States, industry, and academia. We expect the group to report this summer.

Closing

In closing, I hope I have provided a useful update on USDA's food safety initiatives and described the challenges for the future. True progress will require that all of us work together to meet mutual goals. I look forward to working with you to see these goals become reality.

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